tup: sequence of ndarrays. 1D arrays must have same length, arrays must have the same shape along with all the axis.
Row-wise stacked arrays
Code # 1: Explanation of row_stack ()
arr: [  ] arr1: [ [ 2] ]
Code # 2: stron g> Error generated with row_stack ()
ValueError: all the input array dimensions except for the concatenation axis must match exactly.